Gyrus postcentralis

The postcentral gyrus lies in the parietal lobe, posterior to the central sulcus. It is the site of the primary somatosensory cortex. The somatosensory homunculus is the representation of the distribution of the contralateral body parts on the gyrus.

Blood supply

The main blood supply is from the anterior cerebral artery (ACA) and the middle cerebral artery (MCA).

The medial portion of the postcentral gyrus is supplied by the ACA. The convexity of the postcentral gyrus is supplied by the MCA.

Related pathology

Compromise of either the ACA or MCA blood supply can lead to contralateral sensory deficits as part of ACA syndrome.

Practical points

On sagittal images, the thin postcentral gyrus sign  can be used to identify the postcentral gyrus. This sign states that the sagittal width of the postcentral gyrus is thinner than the precentral gyrus. Thus, the thin vertical gyrus and sulcus posterior the central sulcus are the postcentral gyrus and sulcus.